I believe that in this forum we assume temperature is a variable that must be accommodated in design, unless otherwise stated. I cannot imagine why any unstated temperature would be assumed to be 0 oC. I suppose sea-level atmospheric pressure is often assumed, but where it matters, it should not be assumed at all.
You might want to consider the "triple point" of water, below which pressure "melting point" is meaningless and the "freezing point" varies considerably with pressure.
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